Manufactured from spring stainless steel Mini shark-fin tabs - rather than notches.
Fits most European style band spearguns. Available in 1/4", 17/64", 9/32" diameter

Tahitian Flopper (barbs on top)
Hawaiian Flopper (barbs on bottom)
Threaded (6mm)

front view: (Hawaiian Flopper style & Threaded)

rear view (same on both - different angles)